Exhibit 12.1

Computation of Ratio of Earnings to Fixed Charges

	Six Months Ended June 30,					Fiscal Year Ended December 31,
	2016			2017		2012		2013		2014		2015			2016
	(dollars in millions)
Earnings:
Income (loss) before income taxes	$	(74.4	)	$	20.6	$	63.5	$	35.8	$	32.6	$	(18.6	)	$	(68.7	)
Interest expense		27.4			31.0		43.2		45.1		45.1		52.8			55.9
Portion of rents representative of interest factor		2.1			1.9		5.0		5.0		4.4		4.8			4.2
Adjusted income before income taxes	$	(44.9	)	$	53.5	$	111.7	$	85.9	$	82.1	$	39.0		$	(8.6	)
Fixed Charges:
Interest	$	27.4		$	31.0	$	43.2	$	45.1	$	45.1	$	52.8		$	55.9
Portion of rents representative of interest factor		2.1			1.9		5.0		5.0		4.4		4.8			4.2
Total fixed charges	$	29.5		$	32.9	$	48.2	$	50.1	$	49.5	$	57.6		$	60.1
Ratio of earnings to fixed charges		*			1.6x		2.3x		1.7x		1.7x		*			*
Deficiency	$	74.4			N/A		N/A		N/A		N/A	$	18.6		$	68.7

* Earnings for the period were inadequate to cover fixed charges.